Is there some unspoken rule to not use Esuna/Leech?

[Wizarus]

Neither leeches nor Esuna are adversely affected by Cleric Stance, so I find it's rarely a problem to simply cast if regardless of which stance I'm in. If they're taking damage, that's a different matter, but status effects are plane sailing.

The problem here is that it's rarely just status. At the very least, you're in a position to take a sizable amount of damage when you get hit by it. The is especially true if there is more than one status condition/stacked status.